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arXiv · 2201.02723

Channel induced dynamics of quantum information in mixed state free QFTs

Michal Baczyk
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Abstract

We propose a framework for Quantum Field Theory (QFT) studies that allows us to represent field excitations as quantum channels. We demonstrate inner-workings of the proposed scheme for two universal states: the regularized vacuum state of a one dimensional QFT system and the lattice-regulated Thermofield Double State of two identical free QFTs. We investigate actions of unitary and non-unitary Bosonic Gaussian channels (including Petz Recovery maps). To evaluate and quantify the character of the channel static action and channel induced dynamics we calculate quantum entropies and fidelities.

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Michal Baczyk. 2022-01-08. Channel induced dynamics of quantum information in mixed state free QFTs. https://doi.org/10.1103/physrevd.108.016008

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